Drop peess



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e. W. PEGK. DROP PRESS.

.N0. 51;8.,353..-- p Patented Apr. 17, 1894.

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G W. PEGK.

DROP PRESS. No. 518,353. Patented Apr. 17,1894.

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UNITED STATES PATENT OFFIoE.

GEORGE PECK, OF NEW HAVEN, CONNECTICUT, ASSIGNOR TO THE MiNER & PECK MANUFACTURING COMPANY, OF SAME PLACE.

DROP-PRESS.

Application filed April 18, 1893.

To on whom it may concern.-

Be it known that I, GEORGE W. PEOK, of New Haven, in the county of New Haven and State of Connecticut, have invented certain new and usefulImprovements in Drop-Presses and Drop-Lifters; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to [0 make and use the same.

My invention relates to an improvement in drop presses and drop lifters.

The object of the invention is to provide simple and efiicient means for utilizing the power employed for operating the hammer to slightly raise and lower the hammer as may be necessary to adjust and set the dies and with this end in view the invention consists in the combinations of parts hereinafter de- 2 scribed and pointed out in the claims.

In the accompanying drawings Figure 1 is a view partly in side elevation and partly in vertical section of my improvement. Fig. 2 is a plan view of the lifting mechanism, and

Fig. 3 is an enlarged detail in section.

A represents the bed of a drop litter or press, B the guides, C the removable die, D the screw bolts for adjusting and securing the die in place, E the hammer, F the crank of the lifter, and G the flexible band connecting the hammer and wrist pin of the crank. The crank shaft H is mounted in bearings a, a, formed in the frame I. On the crank shaft H is supported a sleeve 11 to which 5 is secured the driving gear J, and the ratchet gear K. On the crank shaft adjacent to the ratchet gear is fastened an arm L the outer end of which is slightly curved as at c and is provided on its opposite edges with the shoul- 4o ders d, d. Secured to the frame on opposite sides of arm L and in the line of its rotation are the yielding stop plates M, N, each of which is constructed and secured in place in the following manner. Each plate rests at 5 its rear end between upright flanges d, (1,

formed on a bracket 0 and are therebyretained against lateral displacement. The rear end of each plate or bar is constructed with a depending arm at through which is inserted a bolt 6, the head of which rests against the inner side of bracket 0, while on its outer SPECIFICATION forming part of Letters Patent No. 518,353, dated April 17,1894.

serial No. 470,870- (No model.)

end is placeda rubber spring P, which is retained in place by a I washer P and nut P At every revolution of the arm L its lower curved end will engage and depress the free end of the spring plate M and comeinto contact with the outer end of the spring plate N by which the further rotation of the arm is prevented. As the arm travels past the end of the spring plate M, the latter will spring back into its, normal position and hence the outer end of arm L will be retained against movement in either direction by means of the spring plates M, N. The rubberor other springs P allow of a slight endwise yielding movement of the spring plates MN and thus cushion the arm L and relieve the parts of any sudden shocks. To the spring plate N is fastened one end of a rod or band f, the lower end of which is secured to a treadle Q. By depressing the treadle, the free end of a spring plate N may be depressed sufficiently to unlock and release the arm L and allow the hammer to drop. This will result owing to the fact that the crank F and the arm L are relatively arranged on the crank-shaft so that when the arm L is locked between the adjacent ends of the spring plates M, N, the crank arm will be at one side of its dead center and hence on the release of the arm L the hammer will be free to drop.

Arm L has a pin m inserted through its outer end. On the projecting end of the pin is pivoted the pawl nwhich is retained in engagement with the ratchet gear K by means of a spring n. On the frame I at apoint underneath the crank-shaft and adjacent to the ratchet gear is located a releasing cam 0 which engages the projecting end of the pawl at every revolution of the crank-shaft and releases the pawl from engagement with the ratchet gear.

S is the driving shaft having mounted thereon the gear S which meshes with the gear J, and through the latter rotates the crank shaft.

T is a band pulley mounted on the driving shaft so as to rotate freely thereon.

U is a'clutch mounted on the driving shaft so as to be'rotated therewith. Clutch lever Vengages the clutch Uand serves to move it into and out of engagement with the band pulley and thereby engage the band pulley with or disengaging it from the driving shaft.

Instead of employing the construction of clutch shown in the drawings I employ in practice a clutch constructed to engage a flange or rim on the band pulley located near its rim whereby a greater leverage and larger frictional surface contact are insured.

In the operation of the hammer, the clutch lever being operated to lock the band pulley to the driving shaft, the latter through the gearing already described operates to rotate the crank-arm and lift the hammer, when the latter is automatically locked against descent until released by the depression of the treadle. Thus at every revolution of the crank shaft the hammer is raised and allowed to drop a fixed and certain distance and hence the force of the blow delivered by the hammer is fixed and uniform.

I will now explain the special use and merit of the friction clutch in connection with a drop press of the type shown and described.

In the use of a drop press, various and different forms and kinds of dies are employed for the varying work required. In adjusting and setting a die, the hammer must be manipulated by being slightly raised and low ered in order to insure the die being adjusted in exact alignment with the die on the hammer. Ordinarily in the use of drop presses of the type in question, this operation has been effected by raising and lowering the hammer by means of a lever, which owing to the weight of the hammer and to the difficulty of adjusting it in this way, has rendered the work slow and tedious. By means of my improvement I obviate the difficulties above specified. When it is desired to set the dies, the operator by skillfully manipulating the clutch lever is enabled to raise and lower the hammer ever so little as may be necessaryin order to properly set the dies and hence by the use of the friction clutch in connection with the band pulley, the power employed in operating the drop press may be readily utilized in setting the dies.

Having fully described my invention, what I claim as new, and desire to secure by Letters Patent, is-- 1. In a drop press the combination with the dies; hammer, crank shaft, crank, and operating gear and mechanism constructed and adapted to operate substantially as described whereby the hammer is automatically locked in its raised position at every revolution of the crank-shaft, and is released by operating a treadle, of a band pulley a friction-clutch for throwing the baud pulley into and out of engagement with the driving shaft and a lever for operating the clutch, whereby the power employed in operating the press may be utilized to facilitate in setting the dies, substantially as set forth.

2. The combination with a die, hammer, crank shaft, and means connecting a crank on the crank shaft with the hammer, of an arm secured to the crank shaft, yielding stop plates for engaging the arm, a driving and ratchet wheel loosely mounted on this crank shaft, a pawl pivoted to the arm on the crank shaft, a cam for automatically removing the pawl from the ratchet toothed wheel, a drive shaft, gearing, and a clutch on the drive shaft for'regulating the application of power thereto, substantially as set forth.

In testimony whereof I have signed this specification in the presence of two subscribing witnesses.

GEORGE W. PECK.

Witnesses:

LOUIS G. MINER, R. M. DOUGLASS. 

